1. Field of the Invention
This invention relates generally to material mixing systems, and more specifically to an economical continuous material mixing system which is particularly beneficial in the production of liquid de-icer, such as brine for use in the control of ice control.
2. Description of the Prior Art
Brine making equipment is well known in the art. Typical brine making systems use a mixing tank and a storage tank. The mixing tank receives bulk salt and water is pumped into the tank to mix with the salt. The water is pumped into the tank through large water pipes, typically 2 to 2.5 inches in diameter. As the water circulates with the bulk salt, salt is dissolved into the water until the correct salinity is reached.
In one type of system, a flow through system, the salinity of the mixture is controlled by the addition of salt or water to the mixing tank until the correct salinity is reached. An example of a flow through brine making system can be found in U.S. Pat. No. 7,186,390, assigned to Duolift Mfg. Co., Inc.
In another type system, a re-circulation system, the brine mixture is re-circulated back through the salt until the proper salinity is reached. Sensors can be used to indicate the correct salinity. Once the proper salinity is reached, the brine is pumped to a storage tank. U.S. Pat. Nos. 7,810,987; 7,897,022; 8,251,569; and 8,382,364, assigned to Cargill Incorporated, disclose a re-circulation type brine making system.
The problem with the flow through systems is the need to continuously add salt or water to get the correct solution. This requires continuous monitoring by an operator. The problem with re-circulation type systems is their complexity and cost. These systems require complex piping, controls and control valves to sense the salinity and re-route it back through the mixing tank until the correct salinity is obtained. Then, when the correct salinity is obtained, re-route the saline solution to storage tanks.
Another problem with known brine making systems is the need to regularly clean the system. The use of bulk salt leaves salt that has not dissolved and debris that accumulates in the tanks. The need to clean the systems results in down time of the system.